This research consists of four related projects concerning etiology and treatment of sexual dysfunction in married couples. Study I is a comparison of standard therapist-administered therapy with a programmed self-help treatment program involving only minimal patient-therapist interaction. Study II is a comparison of the effectiveness of therapy for sexual dysfunction when administered by a single therapist as compared with a dual sex co-therapy team. Study III is a comparison of dysfunctional patients with a normal control group, on parameters of personality, physiological responsiveness, marital relationship and life history variables. The purpose of this study is to identify the etiological factors in sexual dysfunction. Study IV is a comparison of cases treated successfully and cases which fail to benefit from therapy. The purpose of this study is to attempt to identify factors which predict which patients are a good risk for therapy. Variables studied include marital relationships, personality, sexual problem, life history, and various therapy traits. The overall goal of the research is to further our understanding of the factors involved in development of marital sexual dysfunctions, and of the process which underly efficient and effective therapy for such dysfunctions.